This invention relates generally to a flotation device such as a pontoon log and more particular to a method of manufacturing the device which provides for structural connections between the device and a structure it supports without destroying the watertight integrity of the flotation device.
Pontoon boats, otherwise known as pontoons, using pairs of pontoon logs as flotation devices are a popular recreational water item. At least six manufacturers of pontoons compete for this segment of the water recreation equipment industry. Pontoon boats are used for a number of water sports including skiing and fishing.
Among the present manufacturers of pontoons two approaches are generally taken with respect to the assembly of the pontoon logs. Some of the manufacturers use a generally cylindrical log that must be formed by welding a number of cylindrical sections and end pieces together to form the pontoon log. Other manufacturers use a pontoon log having a generally hull-shaped body with a flat top portion. According to present methods the pontoon log is manufacturered by welding the hull-shaped lower section or body and the flat top section together.
The pontoon logs, no matter their shape, are attached to a pontoon deck by intermediate structural members spanning between the pontoon logs in pairs, threes or the number required to accomodate the size or intended purpose of the pontoon.
At present, in order to assure the watertight integrity of the pontoon log, each penetration of the pontoon log for connection with the intermediate structural member must be caulked after attachment. Thus, each of the rivets, bolts and the like used to attach the pontoon log and pontoon deck together by means of the intermediate structural member results in a hole in the pontoon log requiring caulk. In order to insure the water tight integrity of the pontoon log, the bolts are normally caulked by hand. The existing method and resulting pontoon log are expensive and labor intensive and success cannot be guaranteed in view of the need for manual application of the caulk.
Although it is not nnknown to use a rivet and gasket form of construction for boat hulls in lieu of welding, this method has not found acceptance for use with pontoon logs. The closest known construction of this sort is that revealed by U.S. Pat. No. 3,133,294 which discloses a plastic boat including a plastic hull and deck plate with a gasket sandwiched therebetween and a riveted frame member holding the parts together by conventional connection means. In this form of construction the plastic and frame member are held together by the rivets.
The present pontoon log and method for making the pontoon log solves these and other problems in a manner not disclosed in the known prior art.